This study aims to design and implement a domain-specific computer programming language: the Building Environment Rule and Analysis (BERA) Language. As a result of the growing area of Building Information Modeling (BIM), there has been a need to develop highly customized domain-specific programming languages for handling issues in building models in the architecture, engineering and construction (AEC) industry. The BERA Language attempts to deal with building information models in an intuitive way in order to define and analyze rules in design stages. The application of the BERA Language aims to provide efficiency in defining, analyzing and checking rules. Specific example applications implemented in this dissertation are on the evaluation of two key aspects: building circulation and spatial programming. The objective of this study is to accomplish an effectiveness and ease of use without precise knowledge of general-purpose languages that are conventionally used in BIM software development. To achieve the goal, this study proposes an abstraction of the universe of discourse - it is the BERA Object Model (BOM). It is a human-centered abstraction of complex state of building models rather than the computation-oriented abstraction. By using BOM, users can enjoy the ease of use and portability of BIM data, rather than complex and platform-dependent data structures. This study also has reviewed and demonstrated its potential for extensibility of BOM. Not only its lateral extensions such as structural building elements, but also the vertical extensions such as additional properties for existing BOM objects are good examples. In current BERA Language Tool, many computed and derived properties/relations have been proposed and implemented, as well as some basic data directly from the given building model. Target users of the BERA Language are domain experts such as architects, designers, reviewers, owners, managers, students, etc., rather than BIM software developers. It means that the people who are interested in the building environment rule and analysis are the potential users. The BERA Language Tool comprises many libraries to alleviate common but unnecessary problems and limitations that are encountered when users attempt to analyze and evaluate building models using commercially available tools. Combined with other libraries which populate rich and domain-specific datasets for certain purposes, the BERA Language will be fairly versatile to define rules and analyze various building environmental conditions.

In system identification scenario, the linear approximation of the system modelled by its impulse response, is estimated in real time by gradient type Least Mean Square (LMS) or Recursive Least Squares (RLS) algorithms. In recent applications like acoustic echo cancellation, the order of the impulse response to be estimated is very high, and these traditional approaches are inefficient and real time implementation becomes difficult. Alternatively, the system is modelled by a set of shorter adaptive filters operating in parallel on subsampled signals. This approach, referred to as subband adaptive filtering, is expected to reduce not only the computational complexity but also to improve the convergence rate of the adaptive algorithm. But in practice, different subband adaptive algorithms have to be used to enhance the performance with respect to complexity, convergence rate and processing delay. A single subband adaptive filtering algorithm which outperforms the full band scheme in all applications is yet to be realized. This thesis is intended to study the subband adaptive filtering techniques and explore the possibilities of better algorithms for performance improvement. Three different subband adaptive algorithms have been proposed and their performance have been verified through simulations. These algorithms have been applied to acoustic echo cancellation and EEG artefact minimization problems. Details of the work To start with, the fast FIR filtering scheme introduced by Mou and Duhamel has been generalized. The Perfect Reconstruction Filter Bank (PRFB) is used to model the linear FIR system. The structure offers efficient implementation with reduced arithmetic complexity. By using a PRFB with non adjacent filters non overlapping, many channel filters can be eliminated from the structure. This helps in reducing the complexity of the structure further, but introduces approximation in the model. The modelling error depends on the stop band attenuation of the filters of the PRFB. The error introduced due to approximation is tolerable for applications like acoustic echo cancellation. The filtered output of the modified generalized fast filtering structure is given by (formula) where, Pk(z) is the main channel output, Pk,, k+1 (z) is the output of auxiliary channel filters at the reduced rate, Gk (z) is the kth synthesis filter and M the number of channels in the PRFB. An adaptation scheme is developed for adapting the main channel filters. Auxiliary channel filters are derived from main channel filters. Secondly, the aliasing problem of the classical structure is reduced without using the cross filters. Aliasing components in the estimated signal results in very poor steady state performance in the classical structure. Attempts to eliminate the aliasing have reduced the computation gain margin and the convergence rate. Any attempt to estimate the subband reference signals from the aliased subband input signals results in aliasing. The analysis filter Hk(z) having the following antialiasing property (formula) can avoid aliasing in the input subband signal. The asymmetry of the frequency response prevents the use of real analysis filters. In the investigation presented in this thesis, complex analysis filters and real'synthesis filters are used in the classical structure, to reduce the aliasing errors and to achieve superior convergence rate. PRFB is traditionally used in implementing Interpolated FIR (IFIR) structure. These filters may not be ideal for processing an input signal for an adaptive algorithm. As third contribution, the IFIR structure is modified using discrete finite frames. The model of an FIR filter s is given by Fc, with c = Hs. The columns of the matrix F forms a frame with rows of H as its dual frame. The matrix elements can be arbitrary except that the transformation should be implementable as a filter bank. This freedom is used to optimize the filter bank, with the knowledge of the input statistics, for initial convergence rate enhancement . Next, the proposed subband adaptive algorithms are applied to acoustic echo cancellation problem with realistic parameters. Speech input and sufficiently long Room Impulse Response (RIR) are used in the simulations. The Echo Return Loss Enhancement (ERLE)and the steady state error spectrum are used as performance measures to compare these algorithms with the full band scheme and other representative subband implementations. Finally, Subband adaptive algorithm is used in minimization of EOG (Electrooculogram) artefacts from measured EEG (Electroencephalogram) signal. An IIR filterbank providing sufficient isolation between the frequency bands is used in the modified IFIR structure and this structure has been employed in the artefact minimization scheme. The estimation error in the high frequency range has been reduced and the output signal to noise ratio has been increased by a couple of dB over that of the fullband scheme. Conclusions Efforts to find elegant Subband adaptive filtering algorithms will continue in the future. However, in this thesis, the generalized filtering algorithm could offer gain in filtering complexity of the order of M/2 and reduced misadjustment . The complex classical scheme offered improved convergence rate, reduced misadjustment and computational gains of the order of M/4 . The modifications of the IFIR structure using discrete finite frames made it possible to eliminate the processing delay and enhance the convergence rate. Typical performance of the complex classical case for speech input in a realistic scenario (8 channel case), offers ERLE of more than 45dB. The subband approach to EOG artefact minimization in EEG signal was found to be superior to their fullband counterpart. (Refer PDF file for Formulas)

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Building Information Modeling (BIM) is the latest development in the Architecture, Engineering and Construction (AEC) Industry. This development can be used for planning, design, construction, operation and maintenance of any facility. The majority of the users of BIM technology are architects. Although its benefits had been highlighted and underlined especially in comparison with older developments such us Computer Aided Design (CAD) tools, its implementation is considered still in an early stage due to low adoption from architects. Right now in Sweden and more specifically in the Stockholm area, the construction sector is booming due to the increased demand for housing.  Thus, there is an increased demand for more houses in a shorter time. BIM is a technology that can enhance the society in terms of design and construction with regard to the building environment. This can be achieved by avoiding human errors, decreasing project costs, increasing the productivity and quality, and reducing the project delivery time. Moreover, BIM can assist the management team in maintaining and operating different facilities. The focus of this research is on the barriers to adopting BIM technology in architectural companies. Furthermore, the attempt will be to investigate the individual, organizational and technical aspects that affect BIM adoption.  This study will implement a qualitative research method by in-depth interviewing four professionals in the area of architectural design. This investigation will be driven by the main research question, which is: What are the barriers to adopting Building Information Modeling (BIM) in architectural companies?

In recent years, digital twins (DT) have gained traction in enhancing operation and maintenance procedures across various industrial sectors, such as manufacturing, energy, and aerospace. Yet their utilization remains more limited in the built environment. The aim of this paper is to investigate the current conceptualizations of DTs within the context of the Swedish built environment, shedding light on the maturity of DTs for built assets and the key value drivers influencing their adoption. The study reveals that DTs for built assets are in early developmental stages, lacking the maturity required to encompass the full spectrum of attributes inherent in a conventional DT. Despite stakeholders labeling these initiatives as DTs, our findings indicate a closer alignment with the concept of BIM-based digital models. This observation resonates with existing literature, highlighting the absence of a universally accepted definition for DTs. Within the Operations and Maintenance (O&M) phase, we have identified the following four primary value drivers shaping the adoption of BIM-based DTs: 1) commercial transparency and trusted transactions, 2) efficiency and cost reduction in routine operations, 3) operational continuity, and 4) added services. These findings contribute to the ongoing discourse surrounding the convergence of BIM and DTs, offering insights into the practical implications and value propositions that drive the integration of these technologies within the built environment. / Under de senaste åren har användningen av digitala tvillingar (DT:ar) blivit allt vanligare för drift- och underhållsförfaranden inom olika industrisektorer, såsom tillverkning, energi och flyg- och rymdindustrin. Användningen är dock fortfarande begränsad inom bygg- och fastighetsbranschen. Syftet med denna studie är att undersöka de nuvarande konceptualiseringarna av DT:ar inom ramen för den svenska fastighetsbranschen, belysa mognaden hos tekniken och undersöka de viktigaste värdedrivande faktorerna som påverkar utvecklingen och användningen i drift- och underhåll av fastigheter. Studien visar att användningen av DT:ar i fastighetsbranschen befinner sig i ett tidigt utvecklingsstadie och att begreppet inom industrin inte helt överensstämmer med visionen kring konceptet. Resultaten stämmer överens med befintlig litteratur, som belyser avsaknaden av en allmänt accepterad definition för DT:ar. I drift- och underhållsfasen har vi också identifierat följande fyra primära värdedrivande faktorer för användingen av BIM-baserade DT:ar: 1) kommersiell transparens och pålitliga transaktioner, 2) kostnadsbesparingar i rutinmässigt drift- och underhållsarbete, 3) kontinuerligt driftsarbete, samt 4) tilläggstjänster. Resultaten från denna studie bidrar till den pågående diskussionen om koncepten BIM och DT, och ger ytterligare insikt i de praktiska värdeskapande processerna och belyser användningsområden av DT:ar i fastighetsbranschen.

Health and safety during construction remains a worldwide challenge that the construction industry is facing. The German construction industry recorded an average of 110,000 accidents per year in the period of 2010 to 2019. A discernible trend toward a decrease in occupational accidents is not visible. In this context, traditional safety planning does not seem to be able to guarantee sufficient health and safety during construction. In line with the BIM Roadmap published by the German Ministry of Transport in 2015, it can be recognized that Building Information Modeling (BIM) is supposed to be increasingly used in upcoming years. This paper aims to identify how BIM could positively impact Occupational Health and Safety (OHS) during construction. Therefore, a thesis procedure, combining quantitative and qualitative research with an in depth literature review is introduced. This study reveals a high added value of using BIM for (1) safety rule checking and design validation and (2) safety education, training and communication. BIM as a decision supporting tool has the potential to reduce the underestimation of safety hazards and improve safety reporting, which have been identified as current vulnerabilities in the construction industry. Furthermore, an added benefit to sustainability following the concept of Construction Hazard Prevention through Design (CHPtD) is illustrated. In practice, however, BIM for OSH remains unused, while those working with BIM are not familiar with safety planning. This study indicates that in order to fully utilize the potential of BIM, intuitiveness and standardization is required, while those implementing BIM and those using BIM need to be aware of and willing to exploit the potential of new technologies. The challenge now is to recognize the potential of BIM in relation to OHS and to actively use BIM for health and safety purposes. / Att skapa en säker arbetsmiljö på byggarbetsplatsen är fortfarande en global utmaning för byggbranschen. I den tyska byggbranschen inträffade till exempel i genomsnitt 110 000 olyckor per år under perioden 2010-2019 och det syns ingen märkbar minskning. I detta sammanhang verkar traditionell säkerhetsplanering inte kunna garantera tillräcklig hälsa och säkerhet under byggandet. I samband med den strategiska BIM-implementeringsplanen som publicerades av det tyska transportministeriet 2015 ska Building Information Modeling (BIM) användas i allt större utsträckning under de kommande åren. Syftet med den här artikeln är att identifiera hur BIM skulle kunna ha en positiv inverkan på arbetsmiljö och säkerhet (OHS) på byggarbetsplatsen. Studien kombinerar kvantitativ och kvalitativ forskning med en djupgående litteraturgenomgång. Resultatet visar att det finns ett stort mervärde i att använda BIM för (1) kontroll av säkerhetsregler och validering av konstruktionen och (2) utbildning, träning och kommunikation om säkerhet. BIM som beslutsstöd kan möjliggöra en mer realistisk bedömning av säkerhetsrisker och förbättra säkerhetsrapporteringen, vilket har identifierats som aktuella sårbarheter i byggbranschen. Det finns också fördelar med att implementera konceptet Construction Hazard Prevention through Design (CHPtD). I praktiken är dock BIM för arbetsmiljöfrågor fortfarande oanvänd, samtidigt som de som arbetar med BIM inte är tillräckligt bekanta med säkerhetsaspekter. För att BIM:s potential ska kunna utnyttjas fullt ut krävs en ökad användarvänlighet och standardisering av verktygen. Samtidigt måste de som implementerar och använder BIM vara medvetna om och villiga att utnyttja den nya teknikens potential. Utmaningen är nu att förstå potentialen av BIM för arbetsmiljöaspekter och att proaktivt använda BIM för att öka säkerheten på byggarbetsplatser.

The regional economic community (REC) of the Southern African Development Community (SADC) compri'ses 15 Southern African countries. The' economic and political aspects of regional integration in SADC dictate the pace of integration while the influence of a legal regime for regional integration remains at the periphery. While the SADC Treaty and its Protocol on Trade are clear about the priority of economic integration; the full implementation of SADC's economic integration is still yet to be realised using these legal instruments. Regional economic integration is also a priority at both continental and global level. The legal instruments applicable at these levels are those established through the African Union (AU) and the World Trade Organisation (WTO) respectively. Analysis of these external legal instruments is relevant because SADC Member States are signatories to agreements establishing these organisations·. Thus, rules based trade in SADC should be understood from a regional, continental and global perspective where a community must have well-structured and managed relations between itself and other legal systems as a necessary condition for its effectiveness. These structured relations refers to a legal and institutional framework that defines the relations between community and national laws, spelling out the modalities for implementing community law in Member States, defines the respective competencies of the community and Member States and provide rule based systems for resolution of conflicts. In setting the scene for an in-depth discussion of the legal and institutional framework for regional economic integration in SADC, this study presents the history of SADC, its political and economic characteristics that have shaped the legal aspects of trade within the region, the continent of Africa and the world at large. Within this context, the definition of regional integration is presented from a general and international understanding but ultimately gets narrowed down to what it means for Africa and SADC. The discussion on the · theories behind regional economic integration gives understanding to the integration approach employed in the organisation. South Africa's economic and political leadership is critical in the realisation of economic integration; hence this study acknowledges that without South Africa's full commitment; regional economic integration will suffer .a setback. Besides the challenge of implementing rules based trade in SADC, this study also identifies a number of obstacles to SADC regional economic integration and multiple memberships are identified as a: major stumbling block. A comparative study of SADC's institutional framework with that of the E1;Jropean Union· (EU) is undertaken to establish the rationale behind SADC's choice of utilising the EU model of integration. This study establishes the critical role institutions play in the implementation of treaty obligations as established by the agreements. The main lesson from this comparative study is that the EU institutions are allowed to fulfill their obligations of implementing treaty provisions, while SADC institutions are handicapped. The future of SADC is presented within the context of a set of recommendations that identifies the tripartite free trade area (FTA) that includes the East Africa Community (EAC) and the Common Market for Eastern and Southern Africa (COMESA) as one of viable legal instrument for deeper integration in SADC and the continent of Africa. General recommendations are made on the need for reform of rules and principles that are necessary for the implementation of SADC Treaty regime as well as possible improvements that are important for the full realisation of regional economic integration. / PhD (Law), North-West University, Potchefstroom Campus, 2012

The regional economic community (REC) of the Southern African Development Community (SADC) compri'ses 15 Southern African countries. The' economic and political aspects of regional integration in SADC dictate the pace of integration while the influence of a legal regime for regional integration remains at the periphery. While the SADC Treaty and its Protocol on Trade are clear about the priority of economic integration; the full implementation of SADC's economic integration is still yet to be realised using these legal instruments. Regional economic integration is also a priority at both continental and global level. The legal instruments applicable at these levels are those established through the African Union (AU) and the World Trade Organisation (WTO) respectively. Analysis of these external legal instruments is relevant because SADC Member States are signatories to agreements establishing these organisations·. Thus, rules based trade in SADC should be understood from a regional, continental and global perspective where a community must have well-structured and managed relations between itself and other legal systems as a necessary condition for its effectiveness. These structured relations refers to a legal and institutional framework that defines the relations between community and national laws, spelling out the modalities for implementing community law in Member States, defines the respective competencies of the community and Member States and provide rule based systems for resolution of conflicts. In setting the scene for an in-depth discussion of the legal and institutional framework for regional economic integration in SADC, this study presents the history of SADC, its political and economic characteristics that have shaped the legal aspects of trade within the region, the continent of Africa and the world at large. Within this context, the definition of regional integration is presented from a general and international understanding but ultimately gets narrowed down to what it means for Africa and SADC. The discussion on the · theories behind regional economic integration gives understanding to the integration approach employed in the organisation. South Africa's economic and political leadership is critical in the realisation of economic integration; hence this study acknowledges that without South Africa's full commitment; regional economic integration will suffer .a setback. Besides the challenge of implementing rules based trade in SADC, this study also identifies a number of obstacles to SADC regional economic integration and multiple memberships are identified as a: major stumbling block. A comparative study of SADC's institutional framework with that of the E1;Jropean Union· (EU) is undertaken to establish the rationale behind SADC's choice of utilising the EU model of integration. This study establishes the critical role institutions play in the implementation of treaty obligations as established by the agreements. The main lesson from this comparative study is that the EU institutions are allowed to fulfill their obligations of implementing treaty provisions, while SADC institutions are handicapped. The future of SADC is presented within the context of a set of recommendations that identifies the tripartite free trade area (FTA) that includes the East Africa Community (EAC) and the Common Market for Eastern and Southern Africa (COMESA) as one of viable legal instrument for deeper integration in SADC and the continent of Africa. General recommendations are made on the need for reform of rules and principles that are necessary for the implementation of SADC Treaty regime as well as possible improvements that are important for the full realisation of regional economic integration. / PhD (Law), North-West University, Potchefstroom Campus, 2012

<p>The construction industry contributes significantly to the GDP of the United States, attributing to its growth at an unprecedented rate. Efficient planning on all stages of construction is the only way to combat dynamic obstructions and deliver projects on time. The first element involved in the planning phase deals with the layout of the Construction Site. It significantly regulates the pace at which construction operations function and directly affects the time, cost, and safety linked to the successful delivery of the target project. Hence, it is paramount to ensure that every component of the construction site maneuvers with the utmost productivity. One such equipment that occupies significant attention while carrying out the CSLP process is Tower Crane. Tower crane optimization is pivotal to ensure proper lifting and handling of materials, and warrant conflict-free work zones. This research, therefore, aims to optimize its position by maximizing the lift ability. To achieve the goals, Generative Design- a paradigm that integrates the constructive features of mathematical and visual optimization techniques, is used to develop a relatively comprehensible prototype. The first part of the research, thus, utilized Generative Design on two construction sites- one from the United States and one from India. After implementing the visual programming algorithm, an improvement of 40% was warranted in the lift score. A pool of potential alternatives was explored and supplemented by the trade-off illustrations. The concept of trade-off was substantiated by allowing a framework for prioritization of lift cycles, and facilitating a holistic decision-making process. To evaluate the usability, 12 participants were chosen based on their previous experience with tower crane operations. The participants witnessed a live demonstration of the algorithm, answered a Likert scale questionnaire, and appeared for an open-ended interview to provide feedback about the proposed Generative Design technique. After carrying out narrative analysis for the usability aspect- it has been unanimously observed that the technique has extreme efficiency of usage and can evidently prevent the occurrence of errors. The study concludes by providing recommendations to augment the significance and usability of Generative Design for tower crane position optimization. </p><br>